The invention relates to an electric bus bar, its particular possibilities of use and a method for producing the same.
An electric bus bar, known from patent DE 43 08 735 C1, (corresponding to U.S. Pat. No. 5,399,094), comprises a mechanically and electrically shielded conductive track along which a sliding contact may be placed for undisturbed pick-up of data regardless of the electromagnetic interference-rich surroundings. For this purpose, a metal strip accessible on its surface is embedded in the longitudinal channel of an extruded plastic strip whereby a metal mesh is sealed into said plastic strip along its entire length and width for electrical shielding. The thusly assembled plastic strip is then bent into a C-configuration around the metal strip disposed inside and said C-configuration is subsequently forced radially into a C-shaped support profile made of synthetic material. In fact, the C-configuration expands elastically to some degree but its longitudinal edges form thereby sealing lips to close the radial C-slot along which the longitudinal edges of the metal mesh make contact, if they are not spread out locally by the sliding contact engaging here the metal strip in a radial manner. The support profile, which receives at its inner area the C-configuration of the plastic strip equipped with the metal strip, may be designed to have longitudinally-extending ribs on the outside whose front edges are equipped with E-shaped caps (in cross section) to serve as electric conductors for parallel energy supply.
However, traditional bus barsxe2x80x94making energy availablexe2x80x94consist usually of a support body or yoke that is U-shaped in cross section onto which yoke there are contactable conductors inserted on the inside (meaning between the lateral raised legs) in the form of profiled metal tracks or massive blank wires (without insulation)xe2x80x94or said support body is held in place on the yoke between pegs disposed at a distance apart or between through-running ribs. Such conductors may furnish electric power of considerable magnitudes to the adapters based on their type of cross section, which are selectively and detachably attachable again to the conductors along the support body with non-positive or positive fit to feed light fixtures or (electric) supply outlets. However, the installation and the one-piece production of the conductor is rather costly and labor-intensive from a manufacturing and technical view. Oftentimes, the conductors do not require such large cross-sectional dimensions at all, as in signal nets or data nets, for example, but equipping the pre-manufactured support body profile later on with reliably-contacting thin wires is even more labor intensive.
In recognition of these circumstances, the present invention has as its technical object to achieve an electric conductor structure for bus bars which are easy to manufacture and which are not limited, in particular, to the traditional kind of bus bars but which can be employed universally.
This object is achieved according to the invention a conductor structure employable as a bus bar which comprises an extrusion structure made of plastic profiles combined with one another that can or cannot be metallized (electroplated) and which are produced directly in a common extrusion process as support bodies that cannot be metallized having conductor strips embedded therein that can be metallized. The here so-called conductor strips are not electric conductors at first, but they become electric conductors through metallizing of the outer surfaces that are exposed on the surface of the support body. There is great freedom given in the design of the cross-sectional geometry. For instance, the conductor strip could be in the form of longitudinal ribs on a core encased by a support body that cannot be metallized whereby said core penetrates with said ribs the casing in a cross-sectional star-like manner into the plane of the outer surface of said casing. The core of the conductor strip may also be hollow for constructional reasons, or to save material, or to be of lighter weight, and the inner surface of the casing can thereby be additionally metallized. This metallized coating may thereby be disposed in circumferential direction and can be insulated against one another and extend sectional in the form of strips parallel to the core axis of the conductors so that the support body, which means the casing that cannot be metallized, also penetrates in the form of ribs to the inner surface of the hollow core.
These profiles may be employed as traditional bus bars for lighting or data transmission requirements, for example. However, unconventional uses are of more interest economically, as for dual use to a certain extent, such as shielded and here externally accessible transmission of sensor information and control data along the inner surface of a tube used as a medium channel, for instancexe2x80x94or being used inconspicuously in the interior angle area of cross-sectional convex covers used as building material, along support columns and crossheads in standard building installation, or in modular units having traditionally equipped cable channels.
For the purpose of metallizing the exposed surfaces of the conductor strips, the thusly combined exposed extrusion structure can be treated in a single operation in a continuous electroplating process, while piece goods, for example, are electroplated piece by piece in the traditional manner. During the electroplating process, electric-conductive metallization occurs only next to the surfaces of the conductor strips that cannot be electroplated (which means, an exposed area of the conductor next to the electric insulated surroundings), which represents therefore the electric conductive structure.
A conductor structure, which is suitable as an electric bus bar for low to medium current magnitudes, can be produced in an extremely cost-effective manner by a multi-component extrusion process whereby a support body is extruded that is made of electric insulating thermoplastic synthetic material which cannot be metallized and which has continuous conductor strips embedded made of thermoplastic synthetic material that can be metallized, in contrast; whereby there are inevitably and selectively metallized for carrying current (by way of electroplating) only the surfaces of the conductor strips that are exposed from the insulating surroundings of the support body, whereby ohmic contact can be made with said surfaces of the conductor strip by means of adapters, for instance.